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[Author] Hiroshi NAKAJIMA(7hit)

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  • A Fingerprint Matching Algorithm Using Phase-Only Correlation

    Koichi ITO  Hiroshi NAKAJIMA  Koji KOBAYASHI  Takafumi AOKI  Tatsuo HIGUCHI  

     
    PAPER-Digital Signal Processing for Pattern Recognition

      Vol:
    E87-A No:3
      Page(s):
    682-691

    This paper presents an algorithm for fingerprint matching using the Phase-Only Correlation (POC) function. One of the most difficult problems in human identification by fingerprints has been that the matching performance is significantly influenced by fingertip surface condition, which may vary depending on environmental or personal causes. This paper proposes a new fingerprint matching algorithm using phase spectra of fingerprint images. The proposed algorithm is highly robust against fingerprint image degradation due to inadequate fingertip conditions. A set of experiments is carried out using fingerprint images captured by a pressure sensitive fingerprint sensor. The proposed algorithm exhibits efficient identification performance even for difficult fingerprint images that could not be identified by the conventional matching algorithms.

  • An Ultrasonic and Air Pressure Sensing System for Detection of Behavior before Getting out of Bed Aided by Fuzzy Theory

    Hayato YAMAGUCHI  Hiroshi NAKAJIMA  Kazuhiko TANIGUCHI  Syoji KOBASHI  Yutaka HATA  

     
    PAPER-Computation and Computational Models

      Vol:
    E93-D No:3
      Page(s):
    542-549

    This paper proposes a sensing system for a behavior detection system using an ultrasonic oscillosensor and an air pressure sensor. The ultrasonic oscillosensor sensor has a cylindrical tank filled with water. It detects the vibration of the target object from the signal reflected from the water surface. This sensor can detect a biological vibration by setting to the bottom bed frame. The air pressure sensor consists of a polypropylene sheet and an air pressure sensor, and detects the pressure information by setting under the bed's mattress. An increase (decrease) in the load placed on the bed is detected by the increase (decrease) in the pressure of the air held in the tube attached to the sheet. We propose a behavior detection system using both sensors, complementally. The system recognizes three states (nobody in bed, keeping quiet in bed, moving in bed) using both sensors, and we detect the behavior before getting out of bed by recognized these states. Fuzzy logic plays a primary role in the system. As the fundamental experiment, we applied the system to five healthy volunteers, the system successfully recognized three states, and detected the behavior before getting out of bed. As the clinical experiment, we applied the system to four elderly patients with dementia, the system exactly detected the behavior before getting out of the bed with enough time for medical care support.

  • A Survey of Intelligent Computing in Medical and Health Care System Open Access

    Yutaka HATA  Hiroshi NAKAJIMA  

     
    INVITED PAPER

      Vol:
    E97-D No:9
      Page(s):
    2218-2225

    This paper gives a survey of intelligent computational techniques in medical and health care system. First, we briefly describe diagnosable techniques in medical image processing. Next, we demonstrate two ultrasonic surgery support systems for orthopedic and rectum cancer surgeons. In them, intelligent computational technique plays a primary role. Third, computational techniques are introduced in human health care system. Usually, this goal is not to apply clinical treatment but to home use to pay consciousness to health. In it, a simple ECG and respiration meter are introduced with a mat sheet which detects heart rate and respiration. Finally, a medical big data application is introduced, that is, body weight prediction is shown based on autoregressive model. Thus, we show that intelligent computing is effective and essential in modern medical and health care system.

  • Score-Level Fusion of Phase-Based and Feature-Based Fingerprint Matching Algorithms

    Koichi ITO  Ayumi MORITA  Takafumi AOKI  Hiroshi NAKAJIMA  Koji KOBAYASHI  Tatsuo HIGUCHI  

     
    PAPER-Image

      Vol:
    E93-A No:3
      Page(s):
    607-616

    This paper proposes an efficient fingerprint recognition algorithm combining phase-based image matching and feature-based matching. In our previous work, we have already proposed an efficient fingerprint recognition algorithm using Phase-Only Correlation (POC), and developed commercial fingerprint verification units for access control applications. The use of Fourier phase information of fingerprint images makes it possible to achieve robust recognition for weakly impressed, low-quality fingerprint images. This paper presents an idea of improving the performance of POC-based fingerprint matching by combining it with feature-based matching, where feature-based matching is introduced in order to improve recognition efficiency for images with nonlinear distortion. Experimental evaluation using two different types of fingerprint image databases demonstrates efficient recognition performance of the combination of the POC-based algorithm and the feature-based algorithm.

  • A Passive 3D Face Recognition System and Its Performance Evaluation

    Akihiro HAYASAKA  Takuma SHIBAHARA  Koichi ITO  Takafumi AOKI  Hiroshi NAKAJIMA  Koji KOBAYASHI  

     
    PAPER

      Vol:
    E91-A No:8
      Page(s):
    1974-1981

    This paper proposes a three-dimensional (3D) face recognition system using passive stereo vision. So far, the reported 3D face recognition techniques have used active 3D measurement methods to capture high-quality 3D facial information. However, active methods employ structured illumination (structure projection, phase shift, moire topography, etc.) or laser scanning, which is not desirable in many human recognition applications. Addressing this problem, we propose a face recognition system that uses (i) passive stereo vision to capture 3D facial information and (ii) 3D matching using an ICP (Iterative Closest Point) algorithm with its improvement techniques. Experimental evaluation demonstrates efficient recognition performance of the proposed system compared with an active 3D face recognition system and a passive 3D face recognition system employing the original ICP algorithm.

  • A Palmprint Recognition Algorithm Using Phase-Only Correlation

    Koichi ITO  Takafumi AOKI  Hiroshi NAKAJIMA  Koji KOBAYASHI  Tatsuo HIGUCHI  

     
    PAPER

      Vol:
    E91-A No:4
      Page(s):
    1023-1030

    This paper presents a palmprint recognition algorithm using Phase-Only Correlation (POC). The use of phase components in 2D (two-dimensional) discrete Fourier transforms of palmprint images makes it possible to achieve highly robust image registration and matching. In the proposed algorithm, POC is used to align scaling, rotation and translation between two palmprint images, and evaluate similarity between them. Experimental evaluation using a palmprint image database clearly demonstrates efficient matching performance of the proposed algorithm.

  • A Robust 3D Face Recognition Algorithm Using Passive Stereo Vision

    Akihiro HAYASAKA  Koichi ITO  Takafumi AOKI  Hiroshi NAKAJIMA  Koji KOBAYASHI  

     
    PAPER

      Vol:
    E92-A No:4
      Page(s):
    1047-1055

    The recognition performance of the conventional 3D face recognition algorithm using ICP (Iterative Closest Point) is degraded for the 3D face data with expression changes. Addressing this problem, we consider the use of the expression-invariant local regions of a face. We find the expression-invariant regions through the distance analysis between 3D face data with the neutral expression and smile, and propose a robust 3D face recognition algorithm using passive stereo vision. We demonstrate efficient recognition performance of the proposed algorithm compared with the conventional ICP-based algorithm through the experiment using a stereo face image database which includes the face images with expression changes.